How to delete unwanted email without downloading it?

In the ongoing (endless) battle against spam, I am trying to create filters
to block as much of this garbage as possible, but I can't figure out how to
get the Kmail "Configure POP filters" to "Delete mail from server" without
downloading it from my email service provider to my system.

What am I doing wrong?

I choose "Match any of the following" select "Subject" and "contains" and
enter a word or phrase such as "microcap" or "Small Stocks" and for the
filter action, I choose "Delete mail from server", then click "Apply" and "OK"
... but this does not stop the identified subjects from being downloaded to
my system.

Why?

How can I get this to work?

---------------------------------------------------
PLUG-discuss mailing list - PLUG-discuss@lists.plug.phoenix.az.us
To subscribe, unsubscribe, or to change you mail settings:
http://lists.PLUG.phoenix.az.us/mailman/listinfo/plug-discuss